First off you’re doing too much too soon. Going from nothing to 4/5 days in a row!? Fair play to be that motivated to get out and running, but slow down or your body will just give in by way of injury, which it already has unfortunately. One or two runs a week is plenty for now and increase your distances over time (don’t mind the 10% rule).

If youre mad to get out and moving then crosstrain. Which also leads to my next point. Knee pain generally comes from muscle imbalances in your quads, hamstrings and calves so it might be a good idea to do a bit of strength work to strengthen these muscles. And then if you want to build up your fitness and grow the engine while injured, air/assault bikes are amazing at building up your cardio, swim, go to a few spin classes or get out on a bike or get on a rowing machine. Try different things, pick one or a few of them and you will see results!